1、Designation: D 6133 02Standard Test Method forAcetone, p-Chlorobenzotrifluoride, Methyl Acetate or t-ButylAcetate Content of Solventborne and Waterborne Paints,Coatings, Resins, and Raw Materials by Direct Injection Intoa Gas Chromatograph1This standard is issued under the fixed designation D 6133;
2、the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.
3、1. Scope1.1 This test method is for the determination of the total-concentration of acetone, p-chlorobenzotrifluoride, methyl ac-etate, or t-butyl acetate, or combination of any of the four, insolvent-reducible and water-reducible paints, coatings, resins,and raw materials. Because unknown compounds
4、 that co-elutewith the analyte being measured or with the internal standard,will lead to erroneous results, this test method should only beused for materials of known composition so that the possibilityof interferences can be eliminated. The established workingrange of this test method is from 1 % t
5、o 100 % for each analyteby weight.1.2 The values stated in SI units are to be regarded as thestandard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and he
6、alth practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:D 3271 Practice for Direct Injection of Solvent-ReduciblePaints into a Gas Chromatograph for Solvent Analysis2D 3272 Practice for Vacuum Distillation of Solvents fromSolve
7、nt-Reducible Paints for Analysis2D 6438 Test Method for Acetone, Methyl Acetate, andParachlorobenzotrifluoride Content of Paints and Coatingsby Solid Phase Microextraction-Gas Chromatography2E 177 Practice for Use of the Terms Precision and Bias inASTM Test Methods3E 691 Practice for Conducting an I
8、nterlaboratory Study toDetermine the Precision of a Test Method33. Summary of Test Method3.1 A suitable aliquot of whole paint is internally standard-ized, diluted with an appropriate solvent, and then injected intoa gas chromatographic column that separates the chosenanalytes from other volatile co
9、mponents. The analyte content isdetermined from area calculations of the materials producingpeaks on the chromatogram.4. Significance and Use4.1 With the need to calculate volatile organic content(VOC) of paints, and with acetone, p-chlorobenzotrifluoride,methyl acetate and t-butyl acetate4considere
10、d as exemptvolatile compounds, it is necessary to know the content ofthese analytes. This gas chromatographic test method providesa relatively simple and direct way to determine their content.However, because the detectors used in this test method are notselective, and because some coatings are very
11、 complex mix-tures, compounds may be present in the sample that coelutewith the analyte, giving a result that is erroneously high. Or acomponent may elute with the internal standard, giving a resultthat is erroneously low. It is therefore important to know thecomposition of the sample to ensure that
12、 there are no interfer-ences, under the analysis conditions used. Test Method D 6438employs mass-spectral detection of analytes and may be usedas an alternative method.5. Apparatus5.1 Gas ChromatographAny instrument with temperatureprogramming capability may be used. It should be equippedwith a flam
13、e ionization detector (see Table 1).5.2 ColumnAny column that provides baseline separationof the analyte of interest (acetone, p-chlorobenzotrifluoride,methyl acetate or t-butyl acetate), the internal standard, and anyvolatile present in the samples may be used. It should beunderstood that column pe
14、rformance may be influenced bymanufacturing conditions, such as type of deactivation and1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofD01.21 on Chemical Analysis of Paints and Paint Mater
15、ials.Current edition approved Dec. 10, 2002. Published February 2003. Originallyapproved in 1997. Last previous edition approved in 2000 as D 6133 00.2Annual Book of ASTM Standards, Vol 06.01.3Annual Book of ASTM Standards, Vol 14.02.4At the time of the revision of this test method, t-butyl acetate
16、was not yetapproved as an exempt solvent, but was under review by the USEPA and wasexpected to be approved. Therefore, it has been included in this test method.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.chemical bonding/crosslin
17、king used. One or more of thefollowing column types may be used. In terms of durability andover all efficiency, a bonded phase poly (5 % phenyl 95 %dimethylsiloxane) type of column should be considered first.(Any reference to specific product brands does not indicate anendorsement for that particula
18、r brand of column).5.2.1 Capillary, 25 to 60 m, 0.25 mm-inside diameter, 0.25to 1.0-m film thickness, fused silica bonded phase poly (5 %phenyl 95 % dimethylsiloxane (DB-5, HP-5, Rtx-5, Ultra-2,BP-5, CP-Sil 8 CB, etc.).5.2.2 Capillary, 25 to 60 m, 0.25-mm inside diameter, 0.25to 1.0-m film thickness
19、, fused silica FFAP (polyethyleneglycol nitrophthalic acid ester phase).5.2.3 Capillary, 25 to 60 m, 0.25-mm inside diameter, 0.25to 1.4-m film thickness, fused silica bonded phase poly (6 %cyanopropyl/phenyl, 94 % dimethylsiloxane) (DB-624, SPB-624, Rtx-624, etc.).5.3 RecorderA recording potentiome
20、ter with a full-scaledeflection of 1 to 10 mV, full-scale response time of2sorlessand sufficient sensitivity and stability to meet the requirementsof 5.1. The use of a reporting electronic integrator or computerbased data system is preferred.6. Column Peak Interferences6.1 The following compounds ar
21、e known to co-elute orotherwise interfere with the analysis on a DB-5 type column:(a) Acetoneisopropanol, propylene oxide, acetonitrile, and(b) Cyclohexanolsec-amyl acetate.6.2 The following compound is known to co-elute orotherwise interfere with the analysis on an FFAP type column:(a) Cyclohexanol
22、butyl cellosolve.6.3 The analyst must verify that, under the analysis condi-tions being used, none of the components of the sampleinterfere with the analyte being quantitated or with the internalstandard being used.7. Reagents and Materials7.1 Purity of ReagentsUse reagent grade chemicals in alltest
23、s, unless otherwise specified. Other grades may be used,provided it is first ascertained that the reagent is sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination.7.2 Tetrahydrofuran (THF)high performance liquid chro-matography (HPLC) grade, uninhibited.7.3 Cyc
24、lohexanol98+ %.7.4 AcetoneHPLC grade.7.5 p-Chlorobenzotrifluoride98+%.7.6 Methyl Acetate99+%.7.7 t-Butyl Acetate99+%.7.8 Waternanopure.7.9 Chromatography Gases:Helium of 99.9995 % purity or higher.Hydrogen of 99.9995 % minimum purity (see Note 1).Air, “dry” quality, free of hydrocarbons.NOTE 1The pr
25、eferred choice of carrier gas is hydrogen, but helium ornitrogen may also be used. Chromatographic analysis time will increaseand there may be a possible reduction in resolution.7.10 Liquid Charging Devicesmicro syringes of 10 or 25L capacity.7.11 Analytical Balancefour places (0.0001 g).7.12 Sealab
26、le Vials7-mL screw cap.7.13 Medicine Droppers.7.14 Autosampler Vials.7.15 Pipete5-mL glass or autopipete.8. Hazards8.1 Check the suppliers Material Safety Data Sheet(MSDS) on all chemicals before use.9. Preparation of Apparatus9.1 Install the column in the chromatograph following themanufacturers di
27、rections and establish the operating condi-tions required to give the desired separation (see Table 1).Allow sufficient time for the instrument to reach equilibrium asindicated by a stable base line.10. Calibration10.1 Using the information in Table 1 (as a guide), select theconditions of temperatur
28、e and carrier gas flow that give thenecessary resolution of the desired analytes from interferencesin the samples.10.2 Determination of Relative Response FactorsCyclohexanol, or another suitable compound, is used as aninternal standard. The internal standard used should be acompound that is not in t
29、he sample matrix, and does notco-elute with any other component of the sample. Mostanalyses can be done utilizing cyclohexanol for the internalstandard providing it is soluble in the diluent solvent. Theresponse factor for each analyte relative to the standard isdetermined by means of the following
30、procedure. It is goodpractice to determine the relative retention time daily or witheach series of determinations.10.2.1 Prepare a standard with the desired analytes and theinternal standard. This is done in the following manner: A7-mL sealable vial is tared on an analytical balance. Eachdesired ana
31、lyte and the internal standard are added at the 1 drop(;0.02 g) level and their weights recorded. All weights shouldTABLE 1 Suggested Instrument ConditionsDetector Flame Ionization Detection (FID)Hydrogen Flow 30 mL/minAir Flow 400 mL/minMake-up (Helium) 30 mL/minCarrier Gas (Hydrogen) 40 cm/sDetect
32、or Temperature 250CInjection Port Temperature 200CASplit Ratio 50:1BInitial Oven Temperature 40CInitial Temperature Hold Time 5 minProgram Rate 1 4C/minProgram Time 1 5 minFinal Temperature 1 60CProgram Rate 2 20C/minProgram Time 2 8 minFinal Temperature 2 220CFinal Temperature Hold Time 2 minTotal
33、Run Time 20 minInjection Volume 1.0 LAThe injection port temperature can be decreased to permit the analysis ofthermally unstable samples; however, each case must be individually investigated.BThe split ratio may be adjusted according to the theoretical level of solventcomposition.D6133022be recorde
34、d to 0.1 mg. Deliver 5 mL of dilution solvent (THF)to this vial (see Note 2). Lower concentrations may beachieved through further dilution with THF if necessary.NOTE 2The solvent should always be injected separately for obser-vation of contaminants and possible interference peaks, especially in trac
35、eanalysis. The suggested solvents do not preclude the selection of any othersolvent for dilution at the analysts discretion.10.2.2 Inject a 1.0 L aliquot of the standard mixture intothe injection port of the gas chromatograph. At the end of thechromatographic run, calibrate the integrator by followi
36、ng themanufacturers procedure for internal standard weight percentcalibration. If this capability is not available, refer to thefollowing calculations. See Figs. 1-3 for typical chromato-grams using the three listed columns.10.2.3 The response factor of each analyte is calculated asfollows:Ranalyte5
37、Wi3 AanalyteWanalyte3 Ai(1)where:Ranalyte= response factor for the analyte being calibrated,Wi= weight of internal standard,Wanalyte= weight of the analyte being calibrated,Aanalyte= peak area for the analyte being calibrated, andAi= peak area for the internal standard.11. Procedure11.1 Samples are
38、prepared with respect to the amount of theselected analytes in the sample, or the viscosity, or both. Adiluting solvent must be chosen that satisfactorily dissolves thesample and at the same time does not interfere with or obscurethe analyte peaks in the sample. Most samples are easilydissolved in T
39、HF, while a 50/50 blend of nanopure water andTHF will disperse most latex samples.11.2 The prepared sample must be easily dispensed into thesyringe. For this reason, some samples may need to be dilutedfurther. Best results are obtained when the analyte concentra-tion is reduced to about 1 % in the p
40、repared sample. This isaccomplished by diluting the sample (1 g) with1gofdilutingsolvent for every percent of analyte present in the originalsample.11.3 Inject a 1.0 L aliquot of the prepared sample into thechromatographic column. The reporting integrator will displaythe peak retention times and are
41、as of the analytes and internalstandard. The integrator will report the results directly inweight percentages based on the total sample. If a reportingintegrator is not available, manual calculations can be done.11.4 If the sample contains solvent or monomer peakinterferences (for example on a DB-5
42、column, isopropanol hasthe same retention time as acetone), a second capillary columnwith a different phase (FFAP for example) must be used toachieve adequate separation. If available, mass spectral confir-mation may also be used in place of analysis on a secondcolumn, if the mass spectra are suffic
43、iently different to allowisolation of the compounds of interest.11.5 For difficult or pigmented samples, the samples may becleaned up by vacuum distillation (see Practice D 3272), orcentrifugation.11.6 Samples may also be screened for acetone,p-chlorobenzotrifluoride, methyl acetate, or t-butyl acet
44、atecontent using Practice D 3271.12. Calculation12.1 Calculate the weight percent of any of the analytes inthe sample from data obtained from the sample run (see 11.3)as follows:FIG. 1 GC Trace of Solvent Mix in Tetrahydrofuran (THF) on a 30 m, 0.25 mm ID Column With 5 % Phenyl/95 % Dimethylsiloxane
45、 PhaseD6133023Analyte, % 5Aanalyte3 Wi3 100Ai3 Ws3 Ranalyte(2)where:Aanalyte= area of the analyte peak,Ai= area of the internal standard peak,Wi= weight of internal standard added to the sample,Ws= weight of sample, andRanalyte= response factor for the analyte (determined in10.2.3).13. Precision and
46、 Bias13.1 PrecisionThe precision estimates forp-chlorobenzotrifluoride, t-butyl acetate, methyl acetate, andacetone are based on an interlaboratory study in which 7different laboratories analyzed three times, 4 samples ofvarious solventborne materials containing from 22 to 57 %p-chlorobenzotrifluori
47、de, 8 to 33 % t-butyl acetate, 3 to 35 %methyl acetate, and 3 to 22 % acetone. The results obtainedwere analyzed statistically in accordance with Practice E 691.Precision statistics were calculated for the total mass percent ofeach analyte in the 4 coatings and are presented in Table 2. Theterms rep
48、eatability limit and reproducibility limit are used asspecified in Practice E 177.FIG. 2 GC Trace of Solvent Mix in Tetrahydrofuran (THF) on a 30 m, 0.25 mm ID Column With FFAP PhaseFIG. 3 GC Trace of Solvent Mix in Tetrahydrofuran (THF) on a 60 m, 0.25 mm ID Column With 624 PhaseD613302413.1.1 The
49、average 95 % Repeatability Limit (within labo-ratory) coefficient or variation (relative) for each analyte,which represents the 95 % confidence limit for the differencebetween two determinations in the same laboratory, is given inTable 3.13.1.2 The average 95 % Reproducibility Limit (betweenlaboratories) coefficient of variation (relative) for each analyte,which represents the 95 % confidence limit for the differencebetween two determinations in different laboratories, is givenin Table 3.13.2 BiasBias has not been determined.14. Keywords14.1 a
